Method or process of treating paper



Patented Nov. 9, 1937 UNITED STATES PATENT OFFICE Herman Carew, Easton, iPa., assignor, by mesne assignments, to Dixie-Vortex Company, Chicago, 111., a corporation of Delaware No Drawing. Application May 8, 1934,

Serial No. 724,615

3 Claims.

My invention relates to new and useful improvements in a method or process oi treating paper and more particularly to a method or process of coating containers or receptacles made of 5 paper with parafiin or similar material to make them moisture or water-proof.

The principal object of the invention resides in the method of applying an initial coating of paraflinor similar material to. the container or receptacle to drive ofl. moisture and air and to fill its place with the paraflin which completely surrounds all of the fibres of the paper and actually gets into the fibres themselves and then applying a second coating of paraflin which acts as a surface coating, the coating of parafiin when subjected to normal atmospheric temperatures immediately congealing or solidifying so that a fairly heavy layer or surface of wax remains on the article.

A further object of the invention resides in initially subjecting the container or receptacle to immersion in high temperature paraflin and then subjecting the same to an immersion in low temperature paraifin, the receptacles or containers being moved through the high temperature paraflin at relatively high speed and moved through the low temperature parafiln at a relatively slow speed.

Another object of the invention resides in initially subjecting the receptacles or containers to immersion in high temperature parafiln and then at a later time and at a distant point submitting the same to an immersion in low temperature parafiln.

With the above and other objects in view, which will appear as the description proceeds, my invention consists in the novel method or process which will be later described and set forth in the appended claims and it will be understood that such changes or modifications may be made as will fall within the scope of the claims.

I am aware that it has been old to subject paper receptacles or containers, or the paper from which the receptacles or containers are made to an immersion in high temperature 'paraflln or similar material and that it has also been old to submit said containers or receptacles or the paper from which they are made to an immersion in low temperature paraflin or similar material but so far as I am aware it is new with me to initially submit the paper containers or receptacles, or the paper from which they are made,

to an immersion in high temperature paraflln or similar material and then to immersion in low temperature paraffin or similar material. I have found, in actual practice, when the paper or receptacles are treated as set forth that a uniform coating is applied without cracks or crevices and that the receptacles or containers are made moisture or water-proof and properly maintain the material therein. At the same time the initial treatment or coating may take place at one point, such as the point of manufacture, andrthe second treatment or coating may be applied at a distant point, such as at the point of filling, this last treatment or coating filling any cracks or crevices which might result from shipment or the like and at the same time sterilizing just prior to filling.

In carrying out my invention I preferably provide two tanks, one for high temperature paraiiin and one for low temperature paraflin. The containers or receptacles will be immersed in the parafin within the tanks and will be moved through the high temperature parafiin at a relatively high speed and later through the low temperature paraifin at a relatively slow speed. The high temperature parafiin not only coats the surface of the paper, but actually forces the air and mositure out of the paper so thoroughly that the paladin succeeds in completely surrounding all of the fibres and even gets into the fibres themselves. The treatment in the high temperature parafiin further heats the article being coated to such an extent that most of the surface parafiin drains oil when the article is removed from the parafiln and this initial treatment may be referred to as parchmentizing the paper of the article. After this initial treatment or coating the articles are placed in or submerged in the low temperature paraffin and carried therethrough at a relatively slow speed. This applies a surface coating of parafiln to the article or articles. This low temperature paraffin is in fact just above the melting point of the paramn and when the articles are removed from the parafiinin the normal atmospheric temperature most of the wax on the surface of the article or articles immediately congeals or solidifies, so that a fairly heavy layer or surface paraflin remains on the article. This second coating or treatment will fill any creases or crevices remaining after the initial treatment or coating, the advantages of which will be readily apparent, and at the same time will cover such fibres as may be exposed after initial treatment-or coating and prevent any such fibres contacting with the contents of the receptacles or containers to impair the same.

As previously stated while both the initial and second treatments or coatings may be applied at the same point or location at times it may be desirable to apply the second treatment or coating at a distant point. Where the containers or receptacles are to be filled with liquids, such as milk or the like, it can be appreciated that they must be shipped from the point of manufacture to the point of filling and at times during shipment or handling the coating of parafiin will crack thereby impairing the usefulness. of the containers .or receptacles. If desired when the receptacles or containers are to be used in this manner the initial coating or treatment may be applied at the point of manufacture of the containeis or receptacles and then shipped to the point where they are to be used or filled. At this distant point the second coating or treatment may be applied and this second treatment in which the relatively thick surface coating is ap plied will fill any cracks or crevices which may have occurred during shipment and at the same time during this second treatment or coating the receptacles or containers will be sterilized just prior to filling.

After the second treatment or coating naturally the containers or receptacles will be set in position for filling and there will be a tendency for-a certain amount of the paraflln to fiow towards the normal bottom of the container or receptacle.

ture paraffin or similar material at the point of manufacture of the receptacle and then applying a coating of low temperature parafiin or similar material after shipment to the point of use and just prior to filling, said last application acting to sterilize the receptacle or container just prior to use.

2. The method or process of treating paper receptacles or containers, adapted to be filled at a point removed from the place of manufacture which consists in initially applying high temperature paraflin orsimilar material at the point of manufacture to remove air and moisture from the paper and to'imp'regnate the fibres of the paper, and then applying at the point and time the receptacles or containers are to be filled, a

coating of low temperature paraifin or similar material to fill any cracks or crevices remaining after the initial treatment and shipment to the point of use and sterilizing the receptacles or containers-just prior'to filling.

3. The method or process of treating paper receptacles or containers, adapted to be filled at a point removed from the place of manufacture, which consists in initially applying high temperature paraflln or similar material at the point of manufacture and while the receptacles or containers are being moved at relatively high speed to remove air and moisture from the paper and to impregnate the fibres of the paper, and then applying at the point and time the receptacles or containersare to be filled, and while the recep tacles or containers are being moved at a rela-, tively slow speed, a coating of low temperature paraflin or similar material to fill any cracks or crevices remaining after the initial treatment and shipment to the point of use and sterilizing the receptacles or containers just prior to filling.

HERMAN CAREW. 

